1. Field of the Invention
The present invention relates to footwear, in particular, to a shoe with fitness benefits. The fitness benefits are experienced through a unique walking action in which the foot strike mimics the effect of walking on a sandy beach or on an uneven surface. This is accomplished through a multi-layer, multi-density midsole where the surfaces between midsole layers have one or more convexities and one or more concavities.
2. Description of the Related Art
Shoes are designed for many purposes—from protection on the job to performance on the track or court to special occasions and everyday lifestyle. Shoes have also been used to promote physical health and activity. Increasingly, shoes have given users fitness benefits. Many shoes have attempted to provide users the benefit of improving the user's fitness by simply walking while wearing such shoes. However, there continues to be a need for such shoes that improve the user's health yet are comfortable and easy to use.
Walking is one of the easiest and most beneficial forms of exercise. When done properly and with the appropriate footwear, it strengthens the heart, improves cardiovascular health, increases one's stamina and improves posture. It also helps to strengthen one's muscles and maintain joint flexibility.
Prior art shoes have attempted to improve the user's fitness by mimicking walking barefoot. These shoes have included a midsole made of hard material throughout the entire midsole except for a recess in the rear region of the shoe in which a softer, cushioning material is placed. See, for example, U.S. Pat. No. 6,341,432 to Muller. Such shoes include an abrupt, discrete pivot point on the bottom surface of the midsole in the middle region of the shoe where the cushioning material ends and the hard material of the midsole begins. Consequently, in every step taken during normal walking while wearing such shoes, the user is forced to overcome this abrupt, discrete pivot point. This can result in significant pain and discomfort. See also, for example, U.S. Pat. No. 6,782,639 to Müller.
The present invention aims to provide a way of mimicking walking on a sandy beach or on a giving or uneven surface, while not inducing any significant pain or discomfort from doing so. By mimicking walking on a sandy beach and/or on an uneven surface, the present invention aims to significantly increase the fitness and health benefits of everyday walking by requiring the user to exert additional effort and energy while walking and to use muscles that the user otherwise would not use if wearing ordinary footwear, again all without inducing any substantial pain or discomfort.